Re: Pine 4.33 (at least) URL handler allows embedded commands.

From: zen-parse (zen-parseat_private)
Date: Mon Jan 07 2002 - 00:05:15 PST

  • Next message: Roman Drahtmueller: "Re: Pine 4.33 (at least) URL handler allows embedded commands."

    On Sun, 6 Jan 2002, Michal Zalewski wrote:
    
    > On Sat, 5 Jan 2002, zen-parse wrote:
    > 
    > > Problem:		URL handler allows embedded commands.
    > > 			May allow email viruses of the Outlook kind.
    > 
    > >   http://address/'&/some/program${IFS}with${IFS}arguments&'
    > 
    > Isn't that old news? http://www.securityfocus.com/bid/810
    > 
    > I *can* be wrong, but it looks like it is the same problem...
    
    Not quite, but it seems to be a related problem (ie caused by the shell 
    parsing what it was given).
    
    There is some checking for metacharacters done, and if it has any, it puts 
    a single quote around them. However it doesn't check for another single 
    quote.
    
    And then, on Sun, 6 Jan 2002, Michal Zalewski wrote:
    
    > > Isn't that old news? http://www.securityfocus.com/bid/810 I *can* be
    > > wrong, but it looks like it is the same problem...
    > 
    > Ah ok, it is not extactly the same... they "fixed" it... still, I'm pretty
    > sure I've seen it (things like '`id`') later, in 2000 or 2001 on
    > BUGTRAQ...
    
    What might work as a solution could be changing all "'"s into "'\''"s as
    it does in another part of the code.
    
    Or maybe use a popen that doesn't call a shell. 
    
    Could've been the X-Chat thing you saw, but I wouldn't be too surprised if 
    there were more things like that in various clients that come with URL 
    handlers.
    
    -- zen-parse
    
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